JKhedrup wrote:In terms of termas being practiced nowadays, which one has been around the longest? (ie, revealed the furthest back in history)

Mindrolling keeps the Lama Sangdu going, which was discovered by the early terton Guru Chowang. If you can find someone who is sustaining Nyima Nyangral Ozer's termas, that would probably be the oldest extant. A lot of the stories about Guru RInpoche, Yeshe Tsogyal, the 25 disciples, and so on, that we all take for granted these days, really came to the fore based on the termas of these two.

I have a big gap in knowledge regarding this subject so I am going to try to learn a little bit during the holiday period.

Well, I certainly have huge gaps, too. Going back to the OP, this Saraha Center will eventually fill that gap for us--making Nyingma scholastic studies available in person and on the internet. That is--of course--if people support it financially. If there is a major donor out there who would like to help get it off the ground, this is the time to jump in.

Eugene is a very affordable place to live, and Lama Gyaltsen Rinpoche is an old master with incredible knowledge of the tradition. A great opportunity for young people to come get their education is emerging.

The name came from Dzogsar Khyenstse Rinpoche. As he was leaving Pema Osel Ling after his last visit, he called out the car window "Saraha School."

JKhedrup wrote:Are there ever prophecies about how long certain termas will remain efficacious?

Do older termas have a period where the blessings are not seen as strong due to the passing of time and so the practice of newer ones is more beneficial?

Sorry for my neophyte questions, just beginning to explore this topic of termas a little bit.

Prophesies are a funny thing in the Nyingma. Sometimes the "prophesy" of the terma is itself a terma that may be discovered with the terma it predicts or separately by the same terton. So, some highly regarded termas verified themselves. These things are viewed through the eye of faith.

On the other hand, in Dudjom Lingpa's Namthar--a great read!--he clearly predicted the Chinese invasion almost exactly to the year, 100 years before it happened. Therefore, even this old woman, ruined by science, takes everything Dudjom Lingpa predicted literally.